In a phone conversation, Turkish President Recep Tayyip Erdogan and his Iranian counterpart Hassan Rouhani stressed that their nations plus Russia must work together to make the UN’s Syria cease-fire a reality, said the sources, who asked not to be named due to restrictions on speaking to the media.

The two leaders agreed to accelerate efforts to realize the cease-fire in order to end the tragedy in Eastern Ghouta and deliver humanitarian aid to civilians.

The presidents also exchanged views about the trilateral summit between Turkey, Iran, and Russia set for next month in Istanbul.